Surgical procedures for removing a defective joint and replacing it with a prosthetic joint are well known. Removal of a portion of bone tissue is often necessary to accommodate the prosthetic joint. Conventional bone cutting methods have employed reciprocating saws and guide instruments which align and guide the saw blade to produce the desired cut. Conventional guide instruments must be properly aligned and affixed to the bone itself in order to assure that the cutting process will produce a suitable articular surface for the attachment of the prosthetic joint. Once the cutting guide is properly aligned and affixed to the bone, small adjustments to the alignment and position of the guide instrument with respect to the bone are often desirable.
Milling devices have been developed to mill articular surfaces on bone. Heretofore, the milling devices use alignment guide instruments which are affixed to the bone to position and guide the milling device over the bone surface. Generally, the milling guide instruments include templates which have a track to accommodate the shaft of the milling device. Again, once the milling guide instruments are aligned and attached, lateral adjustments are often desired, and conventional milling guide instruments must be realigned and reattached to accommodate fine adjustments.